<!DOCTYPE html>
<html lang="zh-CN">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>Document</title>
  </head>

  <body>
    <div id="app">
      <!-- <input type="text" v-model="message"> -->
      <!-- v-model原理： -->
      <!-- <input type="text" :value='message' @input='valuChange'> -->
      <input
        type="text"
        :value="message"
        @input="message = $event.target.value"
      />
      <h2>{{message}}</h2>
    </div>

    <script src="../js/vue.js"></script>
    <script>
      const app = new Vue({
        el: '#app',
        data: {
          message: '你好'
        },
        methods: {
          valuChange(event) {
            this.message = event.target.value
          }
        }
      })
    </script>
  </body>
</html>
